Researchers were surprised how well these solar cells worked in greenhouses. These new solar panels can generate power without affecting crops. (Photo from mustafagull/E+/Getty Images)
Greenhouses are a more efficient and reliable way to produce corps. They even offer more growth cycles per year. But one of the drawbacks is increased room temperature from insolation. While it can be beneficial in cold weather, it can result in overheating during warm months. Solar panels can help with the issue, but there has to be enough sunlight for the panels and the crops for them to be effective. Researchers from North Carolina State University addressed this issue with semi-transparent solar cells that generate power without affecting the growth and health of plants inside.
Unlike traditional silicon-based solar panels, these are semi-transparent organic solar cells (ST-OSCs). These solar panels are more flexible than others to allow adjustment of wavelengths of the light they harvest. This makes them ideal for greenhouse roofs.
Researchers tested the panels using groups of red leaf lettuce under various types of glass and different wavelengths of light for 30 days. They then monitored the health of the plants taking note of several indicators, including the size of leaves, weight, level of antioxidants, and CO2 absorbed. Results showed no major difference in the lettuce. They grew the same no matter how much light they absorbed.
"We were a little surprised – there was no real reduction in plant growth or health," says plant biologist Heike Sederoff from North Carolina State University. "It means the idea of integrating transparent solar cells into greenhouses can be done."
These are promising results as they can help regulate internal temperatures for greenhouses. Previous research shows ST-OSCs can reduce the carbon footprint of greenhouses by powering them in warm and moderate climates. These panels act as semiconductors and can help keep greenhouses warmer in winter and cooler in summer. But the work isn't over yet. Next, researchers will test the ST-OSCs with other plants and crops – tomatoes are next in line.
"I think that interest is only going to grow," says mechanical and aerospace engineer Brendan O'Connor from North Carolina State University. "We've seen enough proof-of-concept prototypes to know this technology is feasible in principle; we just need to see a company take the leap and begin producing to scale."
Have a story tip? Message me at: http://twitter.com/Cabe_Atwell